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EC-444
DTC P0448 EVAP CANISTER VENT CONTROL VALVE
Revision: 2006 November2007 350Z
DTC P0448 EVAP CANISTER VENT CONTROL VALVEPFP:16935
Component DescriptionNBS000FM
The EVAP canister vent control valve is located on the EVAP canis-
ter and is used to seal the canister vent.
This solenoid valve responds to signals from the ECM. When the
ECM sends an ON signal, the coil in the solenoid valve is energized.
A plunger will then move to seal the canister vent. The ability to seal
the vent is necessary for the on board diagnosis of other evaporative
emission control system components.
This solenoid valve is used only for diagnosis, and usually remains
opened.
When the vent is closed, under normal purge conditions, the evapo-
rative emission control system is depressurized and allows “EVAP
Control System” diagnosis.
CONSULT-III Reference Value in Data Monitor ModeNBS000FN
Specification data are reference values.
On Board Diagnosis LogicNBS000FO
PBIB1263E
PBIB1086E
MONITOR ITEM CONDITION SPECIFICATION
VENT CONT/V
Ignition switch: ON OFF
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0448
0448EVAP canister vent con-
trol valve closeEVAP canister vent control valve remains
closed under specified driving conditions.
EVAP canister vent control valve
EVAP control system pressure sensor
and the circuit
Blocked rubber tube to EVAP canister
vent control valve
EVAP canister is saturated with water
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EC-448
DTC P0448 EVAP CANISTER VENT CONTROL VALVE
Revision: 2006 November2007 350Z
3. CHECK IF EVAP CANISTER SATURATED WITH WATER
1. Remove EVAP canister with EVAP canister vent control valve and EVAP control system pressure sensor
attached.
2. Does water drain from the EVAP canister?
OK or NG
OK >> GO TO 4.
NG >> GO TO 6.
4. CHECK EVAP CANISTER
Weigh the EVAP canister with the EVAP canister vent control valve and EVAP control system pressure sensor
attached.
The weight should be less than 2.2 kg (4.9 lb).
OK or NG
OK >> GO TO 6.
NG >> GO TO 5.
5. DETECT MALFUNCTIONING PART
Check the following.
EVAP canister for damage
EVAP hose between EVAP canister and vehicle frame for clogging or poor connection
>> Repair hose or replace EVAP canister.
6. CHECK EVAP CONTROL SYSTEM PRESSURE SENSOR CONNECTOR
1. Disconnect EVAP control system pressure sensor harness connector.
2. Check connectors for water.
OK or NG
OK >> GO TO 7.
NG >> Replace EVAP control system pressure sensor.
7. CHECK EVAP CONTROL SYSTEM PRESSURE SENSOR
Refer to EC-455, "
Component Inspection" .
OK or NG
OK >> GO TO 8.
NG >> Replace EVAP control system pressure sensor.
8. CHECK INTERMITTENT INCIDENT
Refer to EC-141, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
>>INSPECTION END
PBIB1031E
Water should not exist.
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EC-450
DTC P0451 EVAP CONTROL SYSTEM PRESSURE SENSOR
Revision: 2006 November2007 350Z
DTC P0451 EVAP CONTROL SYSTEM PRESSURE SENSORPFP:22365
Component DescriptionNBS0009B
The EVAP control system pressure sensor detects pressure in the purge line. The sensor output voltage to the
ECM increases as pressure increases.
CONSULT-III Reference Value in Data Monitor ModeNBS0009C
Specification data are reference values.
On Board Diagnosis LogicNBS0009D
PBIB1086E
PBIB1207E
MONITOR ITEM CONDITION SPECIFICATION
EVAP SYS PRES
Ignition switch: ON Approx. 1.8 - 4.8V
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0451
0451EVAP control system
pressure sensor perfor-
manceECM detects a sloshing signal from the EVAP
control system pressure sensor
Harness or connectors
(EVAP control system pressure sensor
circuit is shorted.)
[CKP sensor (POS) circuit is shorted.]
[CMP sensor (PHASE) (bank 2) circuit is
shorted.]
[EVT control position sensor (bank 2) cir-
cuit is shorted.]
(APP sensor 2 circuit is shorted.)
(Refrigerant pressure sensor circuit is
shorted.)
EVAP control system pressure sensor
Crankshaft position sensor (POS)
Camshaft position sensor (PHASE)
(bank 2)
Exhaust valve timing control position
sensor (bank 2)
Accelerator pedal position sensor
Refrigerant pressure sensor
Page 451 of 720
DTC P0451 EVAP CONTROL SYSTEM PRESSURE SENSOR
EC-451
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Revision: 2006 November2007 350Z
DTC Confirmation ProcedureNBS0009E
NOTE:
If DTC Confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait at
least 10 seconds before conducting the next test.
WITH CONSULT-III
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Start engine and wait at least 40 seconds.
NOTE:
Do not depress accelerator pedal even slightly.
3. Check 1st trip DTC.
4. If 1st trip DTC is detected, go to EC-452, "
Diagnostic Procedure" .
WITH GST
Follow the procedure “WITH CONSULT-III” above.
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EC-452
DTC P0451 EVAP CONTROL SYSTEM PRESSURE SENSOR
Revision: 2006 November2007 350Z
Diagnostic ProcedureNBS0009F
1. CHECK GROUND CONNECTIONS
Models with VDC system, navigation system or telephone
1. Turn ignition switch OFF.
2. Loosen and retighten ground screws on the body. Refer to EC-150, "
Ground Inspection" .
Models without VDC system, navigation system and telephone
1. Turn ignition switch OFF.
2. Loosen and retighten ground screws on the body. Refer to EC-150, "
Ground Inspection" .
OK or NG
OK >> GO TO 2.
NG >> Repair or replace ground connections.
1. Body ground E17 2. Body ground E43 3. Body ground B102
:Vehicle front
1. Body ground E17 2. Body ground E43 3. Body ground F152
(Passenger side view with dash side
finisher removed)
:Vehicle front
PBIB3560E
PBIB3561E
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DTC P0451 EVAP CONTROL SYSTEM PRESSURE SENSOR
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Revision: 2006 November2007 350Z
2. CHECK EVAP CONTROL SYSTEM PRESSURE SENSOR CONNECTOR FOR WATER
1. Disconnect EVAP control system pressure sensor harness connector.
2. Check sensor harness connector for water.
OK or NG
OK >> GO TO 3.
NG >> Repair or replace harness connector.
3. CHECK EVAP CONTROL SYSTEM PRESSURE SENSOR POWER SUPPLY CIRCUIT-I
1. Turn ignition switch ON.
2. Check voltage between EVAP control system pressure sensor
terminal 3 and ground with CONSULT-III or tester.
OK or NG
OK >> GO TO 10.
NG >> GO TO 4.
4. CHECK EVAP CONTROL SYSTEM PRESSURE SENSOR POWER SUPPLY CIRCUIT-II
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check harness continuity between EVAP control system pressure sensor terminal 3 and ECM terminal
107. Refer to Wiring Diagram.
OK or NG
OK >> GO TO 6.
NG >> GO TO 5.
5. DETECT MALFUNCTIONING PART
Check the following.
1. Harness connectors T2, B44
2. Harness connectors B1, M12
3. Harness for open between ECM and EVAP control system pressure sensor.
>> Repair open circuit. Water should not exist.
PBIB1086E
Voltage: Approximately 5V
PBIB0138E
Continuity should exist.
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EC-454
DTC P0451 EVAP CONTROL SYSTEM PRESSURE SENSOR
Revision: 2006 November2007 350Z
6. CHECK EVAP CONTROL SYSTEM PRESSURE SENSOR POWER SUPPLY CIRCUIT-III
Check harness for short to power and short to ground, between the following terminals.
OK or NG
OK >> GO TO 7.
NG >> Repair short to ground or short to power in harness or connectors.
7. CHECK COMPONENTS
Check the following.
Crankshaft position sensor (POS) (Refer to EC-393, "Component Inspection" .)
Camshaft position sensor (PHASE) (bank 2) (Refer to EC-405, "Component Inspection" .)
Exhaust valve timing control position sensor (bank 2) (Refer to EC-539, "Component Inspection" .)
Refrigerant pressure sensor (Refer to AT C - 8 0 , "COMPONENT INSPECTION" .)
OK or NG
OK >> GO TO 8.
NG >> Replace malfunctioning component.
8. CHECK APP SENSOR
Refer to EC-648, "
Component Inspection" .
OK or NG
OK >> GO TO 11.
NG >> GO TO 9.
9. REPLACE ACCELERATOR PEDAL ASSEMBLY
1. Replace accelerator pedal assembly.
2. Perform EC-77, "
Accelerator Pedal Released Position Learning" .
3. Perform EC-77, "
Throttle Valve Closed Position Learning" .
4. Perform EC-77, "
Idle Air Volume Learning" .
>>INSPECTION END
10. CHECK EVAP CONTROL SYSTEM PRESSURE SENSOR
Refer to EC-455, "
Component Inspection" .
OK or NG
OK >> GO TO 11.
NG >> Replace EVAP control system pressure sensor.
11 . CHECK INTERMITTENT INCIDENT
Refer to EC-141, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
Refer to EC-458, "
Wiring Diagram" .
>>INSPECTION END
ECM terminal Sensor terminal Reference Wiring Diagram
46 CKP sensor (POS) terminal 1EC-388
64CMP sensor (PHASE) (bank 2) terminal 1EC-399EVT control position sensor (bank 2) terminal 1EC-532
103 APP sensor terminal 4EC-643
107 EVAP control system pressure sensor terminal 3EC-458
111 Refrigerant pressure sensor 1EC-711
Page 455 of 720
DTC P0451 EVAP CONTROL SYSTEM PRESSURE SENSOR
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Revision: 2006 November2007 350Z
Component InspectionNBS0009G
EVAP CONTROL SYSTEM PRESSURE SENSOR
1. Remove EVAP control system pressure sensor with its harness connector connected from EVAP canister.
Always replace O-ring with a new one.
2. Install a vacuum pump to EVAP control system pressure sensor.
3. Turn ignition switch ON and check output voltage between ECM
terminal 102 and ground under the following conditions.
CAUTION:
Always calibrate the vacuum pump gauge when using it.
Do not apply below -93.3 kPa (-700 mmHg, -27.56 inHg) or
pressure over 101.3 kPa (760 mmHg, 29.92 inHg).
4. If NG, replace EVAP control system pressure sensor.
Applied vacuum kPa
(mmHg, inHg)Voltage V
Not applied 1.8 - 4.8
-26.7 (-200, -7.87) 2.1 to 2.5V lower than above value
PBIB3573E